update ts, uglify and fix IE8 issues

JavaScript/JavaScriptSDK/Util.ts

@@ -515,7 +515,7 @@ module Microsoft.ApplicationInsights {
             if (window.addEventListener) {
                 window.addEventListener(eventName, callback, false);
             } else if (window["attachEvent"]) { // For older browsers
-                window["attachEvent"].call(verbEventName, callback);
+                window["attachEvent"](verbEventName, callback);
             } else { // if all else fails
                 return false;
             }

gruntfile.js

@@ -69,7 +69,13 @@ module.exports = function (grunt) {
                 options: {
                     sourceMap: true,
                     sourceMapIncludeSources: true,
-                    sourceMapIn: 'bundle/ai.js.map'
+                    sourceMapIn: 'bundle/ai.js.map',
+                    compress: {
+                        ie8: true
+                    },
+                    mangle: {
+                        ie8: true
+                    }
                 },
             },
             snippet: {

package.json

@@ -26,8 +26,8 @@
     "devDependencies":  {
                             "grunt":  "1.0.1",
                             "grunt-contrib-qunit":  "2.0.0",
-                            "grunt-contrib-uglify":  "2.3.0",
+                            "grunt-contrib-uglify":  "3.1.0",
                             "grunt-ts":  "^6.0.0-beta.15",
-                            "typescript":  "2.4.1"
+                            "typescript":  "2.5.3"
                         }
 }